The present invention relates to a process and an apparatus to apply identification inscriptions on sleeves made of elastomeric material in the production of driving belts.
It is known that in the production of driving belts in general the formation of an axially elongated substantially cylindrical sleeve of elastomeric material incorporating textile reinforcement structures is first provided. This sleeve will be subsequently circumferentially slit at a plurality of axially spaced cuts so as to obtain a number of belts of predetermined width.
However, before said slitting operation the sleeve will be submitted to a marking step in which wordings and inscriptions designed to appear on each of the finished belts are applied to the outer surface thereof, so that said belts may be easily distinguishable from the different types of produced and marketed belts.
In greater detail, usually inscriptions printed on the sleeve give indications relative for example to the brand, model and sizes of the belt, as well as the production date or period of the belt itself.
It will be easily understood that indications relative to the belt brand and type, as well as to size features, are indispensable so that the different types of belt produced may be distinguished from one another in an easy and sure manner.
Indications relative to the production date and period can instead be useful for example when a given lot of belt needs to be withdrawn from the market for example due to defects found out in use, in the belts produced in a particular period.
Currently known methods adapted to apply inscriptions on sleeves are fundamentally based on silk-screen processes.
These processes are necessarily carried out in a substantially manual manner and involve an important waste of time and man-power.
Actually the operator must suitably position a serigraphy stencil on the sleeve being worked in order to subsequently coat a paint layer on the stencil itself. This paint, passing through suitably arranged pervious areas on the serigraphy stencil, will deposit on the sleeve thereby forming the desired inscriptions.
It is to be noted that not only the above silk-screen methods involve important working costs, but also bring about problems related to ecology and health. In fact the unavoidably ejected amounts of paints and solvents are highly polluting.
In addition, these paints and solvents release important amounts of volatile substances which can be injurious to the health of workers carrying out the operation.